It's not going to be covered in the SPD.
"I'm sorry that this didn't happen as quickly as you would have liked but many companies have a policy that they will only send checks to the employer, probably so they don't have to deal with returned checks, etc. It's not a bank account and there are many rules and administrative procedures associated with retirement plans that often cause delays, but it is all perfectly legit. If you don't like that answer, well, you can hire a lawyer but you will only waste your money."